From 280a4aab6661604f1236f7cc4d0b1833a2e68e05 Mon Sep 17 00:00:00 2001
From: Oliver Hamlet <oliver@ortham.io>
Date: Mon, 12 Dec 2022 09:37:53 +0000
Subject: [PATCH] Improve performance of adding group edges

This reduced the time taken when using a very large userlist (featuring
11 group definitions and 1287 group assignments) and 1619 plugins from
332 seconds to 34 seconds.

Without the large userlist, the time taken went from 17 seconds to
1.8 seconds.
---
 src/api/sorting/plugin_graph.cpp | 17 +++++++++++++++--
 src/api/sorting/plugin_graph.h   |  2 ++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/src/api/sorting/plugin_graph.cpp b/src/api/sorting/plugin_graph.cpp
index a5b18d37..72fe2c78 100644
--- a/src/api/sorting/plugin_graph.cpp
+++ b/src/api/sorting/plugin_graph.cpp
@@ -309,6 +309,16 @@ std::optional<vertex_t> PluginGraph::GetVertexByName(
   return std::nullopt;
 }
 
+std::optional<vertex_t> PluginGraph::GetVertexByExactName(
+    const std::string& name) const {
+  const auto it = pluginNameVertexMap.find(name);
+  if (it != pluginNameVertexMap.end()) {
+    return it->second;
+  }
+
+  return std::nullopt;
+}
+
 const PluginSortingData& PluginGraph::GetPlugin(const vertex_t& vertex) const {
   return graph_[vertex];
 }
@@ -441,7 +451,8 @@ void PluginGraph::AddEdge(const vertex_t& fromVertex,
 }
 
 void PluginGraph::AddVertex(const PluginSortingData& plugin) {
-  boost::add_vertex(plugin, graph_);
+  const auto vertex = boost::add_vertex(plugin, graph_);
+  pluginNameVertexMap.emplace(plugin.GetName(), vertex);
 }
 
 void PluginGraph::AddPluginVertices(const Game& game,
@@ -669,7 +680,9 @@ void PluginGraph::AddGroupEdges(
     const auto& toPlugin = GetPlugin(vertex);
 
     for (const auto& pluginName : toPlugin.GetAfterGroupPlugins()) {
-      const auto parentVertex = GetVertexByName(pluginName);
+      // After group plugin names are taken from other PluginSortingData names,
+      // so exact string comparisons can be used.
+      const auto parentVertex = GetVertexByExactName(pluginName);
       if (!parentVertex.has_value()) {
         continue;
       }
diff --git a/src/api/sorting/plugin_graph.h b/src/api/sorting/plugin_graph.h
index 81865add..631ca662 100644
--- a/src/api/sorting/plugin_graph.h
+++ b/src/api/sorting/plugin_graph.h
@@ -65,6 +65,7 @@ public:
   size_t CountVertices() const;
   std::pair<vertex_it, vertex_it> GetVertices() const;
   std::optional<vertex_t> GetVertexByName(const std::string& name) const;
+  std::optional<vertex_t> GetVertexByExactName(const std::string& name) const;
 
   const PluginSortingData& GetPlugin(const vertex_t& vertex) const;
 
@@ -97,6 +98,7 @@ public:
 private:
   RawPluginGraph graph_;
   PathsCache pathsCache_;
+  std::map<std::string, vertex_t> pluginNameVertexMap;
 };
 }